1. Technical Field
The present invention relates to an illuminator and a projector and, more particularly, to a technology of an illuminator that is used with a spatial light modulator.
2. Related Art
A liquid crystal display device, which is used as a spatial light modulator of a projector, converts the polarization state of incident light and carries out modulation. In a case where the liquid crystal display device is used, light outputted from a light source can be efficiently used by converting the light from the light source into a polarization component of a predetermined oscillation direction and supplying the polarization component. JP-A-2004-69996 discloses a method of converting light into a polarization component of a predetermined oscillation direction and supplying the polarization component.
According to the method of JP-A-2004-69996, light from a light source needs to be focused on a surface of a polarizing beam splitter to efficiently polarize the light from the light source. As an emission region of the light source becomes smaller, the incident angle of the light that is incident on the surface of the polarizing beam splitter becomes wider. Accordingly, the light from the light source can be efficiently incident on the polarizing beam splitter. On the other hand, a light source having a large emission region may be used to display a bright image with the projector. Conventionally, as the emission region of the light source becomes larger, it is difficult for the light outputted from the light source to be efficiently incident on the polarizing beam splitter. As a result, it is difficult to reduce a decrease of illumination efficiency that results from adjustment of the polarization direction of light.